A key driver of TB transmission is the significant number of “missed” TB cases who are undiagnosed. In 2013, WHO estimated 3.3 million missing cases of TB. Though South African national guidelines recommend universal TB screening of all individuals presenting to health facilities, TB suspects continue to be missed. We assessed the magnitude of missed pulmonary TB cases presenting at primary health care (PHC) facilities in Buffalo City

A total of 647 individuals were enrolled; 319 with respiratory symptoms and 328 for other health reasons. Of those who attended facilities with respiratory symptoms, 251/319 (78.7%) were screened for TB by clinic staff and 12/319 (3.8%) were asked to provide sputum for testing. Of those who attended for other health reasons and were TB symptomatic, 62/328 (18.9%) were screened for TB and 5/328 (1.5%) were asked to provide sputum for testing. A total of 541 (83.6%) participants provided a sputum sample; 31 (5.7%) tested positive for MTB (n = 27 rifampicin sensitive; n = 3 MDR; n = 1 rifampicin inconclusive). Of those infected with TB, 21 (67.7%) were men, 6 (19.4%) had contact with a known TB patient within the last year, 4 (12.9%) had diabetes mellitus, 7 (22.6%) self-reported HIV infection, and 5 (16.1%) previously had TB. Nineteen (61.3%) of those who tested positive for MTB were screened but not asked to provide sputum for testing by clinic staff. Eighteen (58.1%) of those who tested positive for TB had sought care for respiratory symptoms but were not asked to provide sputum for testing by clinic staff.

Conclusion

Missed screening opportunities within health facilities are contributing to the 3.3 million missing cases of TB. Universal screening within South African PHCs must be conducted as mandated by national guidelines.